Department of Veterinary Population Medicine, University of Minnesota, St. Paul, MN, USA.
Boehringer-Ingelheim Animal Health, Duluth, GA, USA.
Vet Res. 2019 Oct 28;50(1):86. doi: 10.1186/s13567-019-0701-8.
This study investigated the influence of gut microbiome composition in modulating susceptibility to Mycoplasma hyopneumoniae in pigs. Thirty-two conventional M. hyopneumoniae free piglets were randomly selected from six different litters at 3 weeks of age and were experimentally inoculated with M. hyopneumoniae at 8 weeks of age. Lung lesion scores (LS) were recorded 4 weeks post-inoculation (12 weeks of age) from piglet lungs at necropsy. Fecal bacterial community composition of piglets at 3, 8 and 12 weeks of age were targeted by amplifying the V3-V4 region of the 16S rRNA gene. The LS ranged from 0.3 to 43% with an evident clustering of the scores observed in piglets within litters. There were significant differences in species richness and alpha diversity in fecal microbiomes among piglets within litters at different time points (p < 0.05). The dissimilarity matrices indicated that at 3 weeks of age, the fecal microbiota of piglets was more dissimilar compared to those from 8 to 12 weeks of age. Specific groups of bacteria in the gut that might predict the decreased severity of M. hyopneumoniae associated lesions were identified. The microbial shift at 3 weeks of age was observed to be driven by the increase in abundance of the indicator family, Ruminococcaceae in piglets with low LS (p < 0.05). The taxa, Ruminococcus_2 having the highest richness scores, correlated significantly between litters showing stronger associations with the lowest LS (r = -0.49, p = 0.005). These findings suggest that early life gut microbiota can be a potential determinant for M. hyopneumoniae susceptibility in pigs.
本研究调查了肠道微生物群落组成在调节猪对支原体肺炎易感性中的影响。从 6 个不同窝的 32 头 3 周龄常规支原体肺炎自由猪中随机选择，在 8 周龄时用支原体肺炎进行实验接种。在剖检时从仔猪肺部记录接种后 4 周（12 周龄）的肺病变评分（LS）。在 3、8 和 12 周龄时，通过扩增 16S rRNA 基因的 V3-V4 区来靶向仔猪的粪便细菌群落组成。LS 范围为 0.3%至 43%，在同一窝内的仔猪中观察到评分明显聚类。不同时间点同一窝内仔猪粪便微生物群的物种丰富度和 alpha 多样性存在显著差异（p<0.05）。相似性矩阵表明，在 3 周龄时，仔猪的粪便微生物群与 8 至 12 周龄时相比更为不同。确定了可能预测支原体肺炎相关病变严重程度降低的肠道中特定细菌群。在 3 周龄时观察到的微生物群变化是由低 LS（p<0.05）仔猪中指示家族（Ruminococcaceae）丰度增加驱动的。具有最高丰富度评分的 Ruminococcus_2 分类群在显示与最低 LS 更强关联的窝之间呈显著相关（r=-0.49，p=0.005）。这些发现表明，早期生命肠道微生物群可能是猪对支原体肺炎易感性的潜在决定因素。
